A method for afforestation in coastal saline-alkali land

Abstract

This invention provides a method for afforestation in coastal saline-alkali land, including a step of identifying dominant salt-tolerant tree species in the region, a step of identifying dominant native tree species in the region, a step of identifying dominant landscape greening tree species in the region, a step of screening salt-tolerant landscape greening tree species, and a step of propagating rhizosphere microorganisms of salt-tolerant tree species. Then, planting soil is prepared using collected active cultivation substrate and saline-alkali soil at a volume ratio of 3:7 to cultivate the screened salt-tolerant tree species. This invention abandons the simple and crude afforestation methods of the past, selecting suitable dominant tree species based on the characteristics of the afforestation soil and climatic conditions, avoiding huge economic losses and resource waste, and providing a systematic and feasible scientific method for large-scale afforestation, especially in saline-alkali land.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of gardening, and relates to a method for afforestation, in particular to a method for afforestation of coastal saline-alkali soil. BACKGROUND

[0002] China has a long coastline, and a large number of coastal saline-alkali soils are distributed. There are many problems in the afforestation of coastal saline-alkali soil. Low survival rate and low plant diversity are the current situation of the afforestation of coastal saline-alkali soil. Design or construction units carry out large-scale saline-alkali soil planting construction according to the plant planting list provided by the first party, and at the same time, carry out ditching, drainage, planting hole soil improvement, addition of isolation layer and other measures. However, a large number of trees die or weaken after one year or a few years, which causes great economic losses to the society and also slows down the pace of urban ecological civilization construction.

[0003] The plant list provided by the first party may contain a large number of saline-alkali tolerant tree species, and also contain a large number of garden landscape configuration plants. These plants show significant adaptability difference when planted in different climate conditions and different regions.

[0004] How to screen the dominant pioneer tree species suitable for the afforestation of saline-alkali soil in the region is a key factor for the success of the afforestation of saline-alkali soil. The present application screens the tree species suitable for the growth conditions of saline-alkali soil in the region as the target according to the principle of suitable trees for suitable places, and creates the best growth conditions for the tree species. SUMMARY

[0005] In view of the above technical problems in the prior art, the present application provides a method for afforestation of coastal saline-alkali soil, which solves the technical problems of low survival rate and low plant diversity in the prior art.

[0006] The present application provides a method for afforestation of coastal saline-alkali soil, which comprises the following steps:

[0007] 1) a step of finding the dominant saline-alkali tolerant tree species in the region, selecting the representative 1-5 age saline-alkali soil shelter forest dominant tree species in the region, which show the characteristics of vigorous growth, no pests and stable growth, and writing into the saline-alkali soil afforestation saline-alkali tolerant tree species selection list in the region; if there is no 1-5 age forest in the saline-alkali soil in the region, selecting the 6-10 age saline-alkali soil shelter forest dominant tree species in the region, and writing into the saline-alkali soil afforestation saline-alkali tolerant tree species selection list in the region;

[0008] 2) a step of finding the dominant native tree species in the region, the native tree species refers to the native tree species in the region or the introduced tree species which have been introduced for 6-10 years and have been performing well in the local area, and the native tree species in the region which grow vigorously, have no pests and grow stably are written into the native tree species selection list for the afforestation of saline-alkali soil in the region;

[0009] 3) A step of finding the dominant landscape greening tree species in the region. If the salt-alkali land afforestation selection list formed by steps 1) and 2) does not meet the total amount requirement of plant species for large-scale salt-alkali land afforestation, the dominant tree species are extracted from the list of commonly used landscape tree species in the region into the salt-alkali land afforestation landscape greening tree species selection list in the region;

[0010] 4) A step of screening salt-alkali tolerant tree species for salt-alkali land afforestation. The tree species are selected from the list formed in step 3) for salt-alkali tolerance screening, and the salt-alkali tolerant dominant tree species are selected. The tree species preferably include all the tree species in the list of steps 1) and 2), and the remaining part is selected from the list of step 3) in order. Ten 10-year-old or older tree seedlings of each selected tree species are planted in the representative salt-alkali area of the planned afforestation area. Normal drainage ditches are excavated, and the trees are planted on Qingming. The growth conditions of each tree species are observed after Qingming of the next year;

[0011] The selected tree species are divided into four categories: the first category is the "strong salt-alkali tolerant" tree species with a survival rate of 100% and strong growth potential; the second category is the "medium salt-alkali tolerant" tree species with a survival rate of less than 100% but more than 60% and strong growth potential; the third category is the "weak salt-alkali tolerant" tree species with a survival rate of less than 50%; and the fourth category is the alternative tree species with a survival rate of less than 60% but more than 50% and general growth potential;

[0012] If the proportion of "strong salt-alkali tolerant" tree species is more than 50%, all the "strong salt-alkali tolerant" tree species are added to the afforestation list. If the proportion of "strong salt-alkali tolerant" tree species is less than 50% and the target tree species for afforestation is not reached, "medium salt-alkali tolerant" tree species are selected to make up 50% to ensure that the target salt-alkali tolerant tree species are selected;

[0013] 5) A step of expanding the rhizosphere microorganisms of salt-alkali tolerant tree species: the rhizosphere soil of "strong salt-alkali tolerant" tree species and "medium salt-alkali tolerant" tree species in step 4) is taken out, mixed with garden waste or any agricultural and forestry waste compost in a mass ratio of 5:(80-120), and spread on the nursery tray. The rhizosphere soil is sown with strong root system crop seeds, and the nursery tray is irrigated normally. After 3 or 4 weeks, all underground parts including roots and cultivation substrate are harvested and labeled. At the same time, half of the underground parts are collected, and the other half is added with new garden waste to continuously expand the microorganisms and obtain active cultivation substrate;

[0014] 6) The active cultivation substrate of step 5) and the salt-alkali soil of the original habitat of the tree species are mixed in a volume ratio of 3:7 to prepare the planting soil for the selected salt-alkali tolerant tree species.

[0015] Further, the strong root system crop seeds are any one or a combination of two or more of corn, wheat or soybean.

[0016] Further, 100 tree species are selected from the list formed in step 3) for salt-tolerant screening, and 50 salt-tolerant dominant tree species are selected from the 100 tree species; the 100 tree species preferably contain all the tree species in the list in step 1) and step 2), and the insufficient part is selected from the list in step 3) from front to back in turn; 10 strains of 10-year-old or above tree seedlings of each of the 100 tree species are selected, and a total of 1000 strains are planted in a representative area of the saline-alkali land in the afforestation area, normal drainage ditches are excavated, and the trees are planted on Qingming, and the growth conditions of the trees are observed after Qingming of the next year.

[0017] Specifically, the local area refers to a city belonging to the same climate zone along the coast.

[0018] Compared with the prior art, the technical effect of the present application is positive and obvious. The present application discards the simple and rough afforestation method in the past, and selects the suitable afforestation dominant tree species according to the characteristics of the afforestation soil and the climate conditions, thereby avoiding huge economic losses and resource waste, and providing a set of systematic and feasible scientific method for large-scale afforestation, especially for saline-alkali land afforestation. DETAILED DESCRIPTION

[0019] Example 1

[0020] The present application provides a method for afforestation in coastal saline-alkali land, which specifically comprises the following steps:

[0021] 1. Finding the dominant salt-tolerant tree species in the local area: The mature forest of early coastal afforestation in the city often has a single vegetation type and gradually moves away from the coastline. Because of the long growth period, the surface soil is rich in humus, so it presents a relatively stable growth state, and the dominant tree species type is not suitable as a new pioneer candidate species for saline-alkali land afforestation.

[0022] The younger the saline-alkali land, the more representative the tree species, and the better the growth adaptability to the current climate and soil conditions.

[0023] The dominant tree species type in the 1-5 age new saline-alkali land in the local area is selected, which often shows vigorous growth, no insect pests, and stable growth, and is written into the local new saline-alkali land afforestation selection list. The tree species type with weak growth and prone to disease is written into the local new saline-alkali land afforestation prohibited list. If there is no 1-5 age new afforestation in the local saline-alkali land, the dominant tree species type is selected from the latest saline-alkali land in the local area (6-10 age). The local saline-alkali land afforestation tree species type selection list and the prohibited list are prepared.

[0024] 2、Find the local dominant native tree species: the type of tree species in the salt-alkali land afforestation tree species selection list in step 1 is often small in quantity (3-10 species) (related to the local afforestation planning and design), which is not enough to support large-scale (more than 10,000 mu) salt-alkali land afforestation plant selection (50-100 species or more). The local dominant native tree species 10-20 or more can be written into the salt-alkali land afforestation tree species selection list.

[0025] 3、Find the local dominant landscape tree species: the salt-alkali land afforestation tree species selection list (10-30 species) formed in step 2 is still not enough to support large-scale salt-alkali land afforestation plant selection (50-100 species or more). The remaining tree species list is often collected from the local commonly used landscape tree species directory and literature screening. This part of the tree species is used the most and has no salt-alkali land practice data support, which needs to be verified in practice. Landscape trees have rich market nursery resources and are the main force in afforestation, but also the largest casualty group in afforestation. How to scientifically select salt-tolerant landscape trees is the key to successful afforestation.

[0026] 4、Scientifically select salt-tolerant landscape trees: 100 species of dominant landscape trees are selected from the local commonly used landscape tree species directory (obtained from relevant green industry departments or self-research) and literature screening (50 salt-tolerant tree species are selected as the target, and the actual afforestation target is determined according to the needs). Each selected tree species has 10 healthy seedlings (10 years old or older), totaling 1000 seedlings planted in the most severely salt-alkali area of the planned afforestation area. Dig a normal drainage ditch about 1 meter deep without any other improvement measures (soil improvement, fertilization, isolation layer, etc.). Plant on Tomb Sweeping Day and observe the growth of each tree species after Tomb Sweeping Day the next year.

[0027] The selected tree species are divided into four categories: those with 100% survival rate and strong growth are classified as "strong salt-tolerant" tree species; those with more than 60% survival rate and relatively strong growth are classified as "moderate salt-tolerant" tree species; those with less than 50% survival rate are classified as "weak salt-tolerant" tree species; and those with 50%-60% survival rate and average growth are classified as alternative tree species.

[0028] If the "strong salt-tolerant" tree species account for more than 50% (based on 100 species), all "strong salt-tolerant" tree species will be added to the afforestation list. If the "strong salt-tolerant" tree species account for less than 50% and do not meet the afforestation target tree species requirement, "moderate salt-tolerant" tree species will be selected to make up 50% to ensure that 50 salt-tolerant tree species are selected.

[0029] The screening test includes the plants in step 1 and step 2 tree species list, i.e. the existing dominant salt-tolerant tree species and dominant native tree species in the local area. Step four basically scientifically establishes the local salt-alkali land afforestation dominant tree species list, and the total amount of "strong salt-tolerant" tree species should account for 50% or more of the total amount in the later afforestation process.

[0030] 5. The proliferation of rhizosphere microorganisms of salt-tolerant tree species: Tree transplanting, especially on saline-alkali land, plays a key role in the survival and growth of trees. During tree transplanting, root damage is severe, and a large number of symbiotic microorganisms in the rhizosphere and inside the roots are lost, which hinders the subsequent repair. Garden construction personnel occasionally apply beneficial microbial inoculants sold on the market during tree transplanting. The microbial inoculant market is relatively chaotic, the microbial species are single, the efficacy is limited, and the specific matching with the host needs to be considered. Nature is a huge microbial resource library. Due to limited technology, the number of microorganisms isolated by humans is very limited, but this does not prevent humans from using microbial resources.

[0031] The "strong salt-tolerant" tree species and "moderate salt-tolerant" tree species in step 4 have recruited a new population of beneficial microorganisms adapted to the saline-alkali environment in the root soil after a year or more. How to inoculate the new microbial population into the large-scale saline-alkali land afforestation in the later stage is another key factor for successful afforestation.

[0032] The rhizosphere soil (containing a small amount of root system) of the "strong salt-tolerant" tree species and "moderate salt-tolerant" tree species in step 4 is taken out, mixed with garden waste (or any agricultural and forestry waste compost) at a ratio of 5:100 (mass ratio), and spread evenly on the seedling tray. Corn, wheat, soybean, and other crop seeds with strong root systems are sown in the seedling tray, and normal irrigation is carried out. After 3 or 4 weeks, all underground parts including roots (pulverized into 1-2 cm segments) and cultivation substrate are harvested and labeled. At the same time, half of the underground parts can be collected, and the other half can be added with new garden waste to continuously proliferate microorganisms, obtaining active cultivation substrate. This method provides protection for the proliferation and preservation of beneficial microorganisms in the rhizosphere of "strong salt-tolerant" tree species and "moderate salt-tolerant" tree species. The preservation time should not be too long, and it is best to be used up within a year in the planting hole of "strong salt-tolerant" tree species and "moderate salt-tolerant" tree species during afforestation.

[0033] 6. Active cultivation substrate and saline-alkali soil from the original habitat of the tree species are collected to prepare a planting soil at a volume ratio of 3:7 to cultivate and select salt-tolerant tree species.

[0034] Example 2

[0035] Taking 100 mu of Shanghai Jinshan shelter forest afforestation and planning to plant 2000 trees as an example, 20 salt-tolerant tree species are selected from 40 tree species.

[0036] Find the local advantage salt-tolerant tree species Metasequoia glyptostrobus, Pinus elliottii, Taxodium distichum, Cinnamomum camphora, Viburnum dilatatum, etc. 5 kinds; Find the local advantage native tree species Broussonetia papyrifera, Sapium sebiferum, Salix babylonica, Sophora japonica, Melia azedarach, etc. 5 kinds; Find the local advantage landscape tree species Platanus orientalis, Osmanthus fragrans, Fagus engleriana, Koelreuteria paniculata, Cinnamomum camphora, Sapindus saponaria, Celtis sinensis, Pinus massoniana, Cedrus deodara, Populus tremula, Magnolia grandiflora, Michelia figo, Quercus robur, Acer rubrum, Ginkgo biloba, Acer, Maackia, Pterocarya stenoptera, Ilex asprella, Liquidambar formosana, Lonicera japonica, Lycianthes, Rosa chinensis, Syringa vulgaris, Camellia japonica, Meihua, Wintergreen, Albizia, Malus, 30 kinds.

[0037] 40 kinds of tree species are planted in the saline-alkali land of Jinshan (a small representative area is opened in the afforestation destination block), the planting soil of the planting hole is 30% of the volume percentage of garden waste (or agricultural and forestry waste) and 70% of the volume percentage of original habitat saline soil, 10 plants for each, a total of 400 plants.

[0038] After 1 year, the survival rate is counted, of which 5 kinds have a survival rate of 100%, 18 kinds have a survival rate of more than 60%, and 17 kinds have a survival rate of less than 50%.

[0039]

[0040]

[0041] In the later afforestation, 5 kinds of tree species with a survival rate of 100% are planted 500 plants, 100 plants for each; 18 kinds of tree species with a survival rate of less than 100% but more than 60% are selected according to the survival rate from high to low, and the first 15 kinds are selected (because the target is to plant 20 kinds of tree species) 1500 plants, 100 plants for each; After the list of 20 kinds of advantage salt-tolerant tree species is screened out, the preparation of the planting soil in the later period is as follows:

[0042] The rhizosphere soil of the above-mentioned tree species with a survival rate of 100% and the tree species with a survival rate of less than 100% but more than 60% is taken out separately, mixed with 5:100 (mass ratio) of garden waste (or any agricultural and forestry waste compost) to cover the seedling tray, and the seeds of crops with strong root systems such as corn, wheat and soybean are sown in the seedling tray, and the seedlings are normally irrigated. After 3 or 4 weeks, all underground parts including roots (pulverized into 1-2 cm small pieces) and cultivation substrate are harvested and labeled, at the same time, half of the underground parts are collected, the other half is added with new garden waste and mixed to continuously propagate microorganisms, and active cultivation substrate is obtained.

[0043] Then, the above-mentioned collected active cultivation substrate and the original habitat saline soil of the tree species are used to prepare the planting soil for cultivating and screening the salt-tolerant tree species according to the volume ratio of 3:7.

[0044] Through statistics, the total afforestation survival rate reaches more than 80%.

Claims

1. A method of afforesting a coastal saline land, characterized by, Comprising the following steps: 1) a step of finding local dominant salt-tolerant tree species, selecting representative 1-5 age salt-alkali land shelter forest dominant tree species types in the local area, said dominant tree species showing vigorous growth, no insect pests, and stable growth characteristics, and writing into the local salt-alkali land afforestation salt-tolerant tree species selection list; if there is no 1-5 age forest in the local salt-alkali land, selecting 6-10 age salt-alkali land shelter forest dominant tree species types in the local area, and writing into the local salt-alkali land afforestation salt-tolerant tree species selection list; 2) a step of finding local dominant native tree species, native tree species refers to naturally distributed tree species in the local area or introduced 6-10 age tree species that have been performing well in the local area, and writing into the local salt-alkali land afforestation native tree species selection list; 3) a step of finding local dominant landscape greening tree species, if the salt-alkali land afforestation selection list formed by steps 1) and 2) does not meet the total plant species quantity requirement for large-scale salt-alkali land afforestation, extracting dominant tree species from the local commonly used landscape tree species directory into the local salt-alkali land afforestation landscape greening tree species selection list; 4) a step of screening salt-alkali land afforestation salt-tolerant tree species, selecting tree species from the list formed by step 3) for salt-tolerance screening, and selecting salt-tolerant dominant tree species from them; tree species prefer to include all tree species in steps 1) and 2), and then select the remaining part from step 3) in order; for each selected tree species, select 10 or more 10-year-old strong seedlings, plant them in the salt-alkali representative area of the planned afforestation area, dig normal drainage ditches, and plant them on Qingming, then observe the growth of each tree species after Qingming of the next year; The selected tree species are divided into four categories: the first category is "strong salt-tolerant" tree species with 100% survival rate and strong growth; the second category is "moderate salt-tolerant" tree species with survival rate less than 100% but more than 60% and strong growth; the third category is "weak salt-tolerant" tree species with survival rate less than 50%; the fourth category is a standby tree species with survival rate less than 60% but more than 50% and average growth; If the proportion of "strong salt-tolerant" tree species is more than 50%, all "strong salt-tolerant" tree species will be added to the afforestation list; if the proportion of "strong salt-tolerant" tree species is less than 50% and the target tree species quantity for afforestation is not reached, "moderate salt-tolerant" tree species will be selected to make up 50% to ensure that the target salt-tolerant tree species is selected; 5) a step of expanding the rhizosphere microorganisms of salt-tolerant tree species: take the rhizosphere soil and roots of "strong salt-tolerant" and "moderate salt-tolerant" tree species in step 4), mix them with garden waste or any agricultural and forestry waste compost in a mass ratio of 5:(80-120), and spread them evenly in the nursery tray, sow crop seeds with strong roots in the nursery tray, and normally irrigate and cultivate the seedlings, then harvest all underground parts including roots and cultivation substrate after 3 or 4 weeks and mark them, at the same time, collect half of the underground parts, add new garden waste to mix them, and continuously expand the microorganisms to obtain active cultivation substrate; 6) Collect the active cultivation medium and the saline-alkali soil of the tree species natural habitat of step 5) to prepare the planting soil for the screened salt-tolerant tree species according to a volume ratio of 3:

7.

2. The method for afforesting coastal saline-alkali soil according to claim 1, characterized in that, The crop seeds with strong root systems are any one of corn, wheat or soybean or a combination of two or more.

3. The method for afforesting coastal saline-alkali soil according to claim 1, characterized in that, 100 tree species are selected from the list formed in step 3) for salt-tolerant screening, and 50 salt-tolerant dominant tree species are selected from the 100 tree species. The 100 tree species preferably include all the tree species in the list of step 1) and step 2), and the rest is selected from the list of step 3) in order. 10 seedlings of each of the 100 tree species of 10 years or older are selected, and a total of 1000 seedlings are planted in the representative area of the saline-alkali soil in the reforestation area. Normal drainage ditches are excavated, and the seedlings are planted on Qingming. The growth conditions of each tree species are observed after Qingming of the next year.

Images